1. Field of the Invention
The invention relates in general to a key structure, and more particularly to a gas releasable key structure and a keyboard structure using the same.
2. Description of the Related Art
Examples of electronic devices include mobile phones, PDAs, translation machines, notebook computers, and desktop computers, most using physical keys as the communication interface between the user and the electronic devices. Besides, the virtual keys displayed on the touch screen are getting more and more popular but are used in small-sized hand-held devices to fit the requirements of miniaturization. However, physical keys provide the user with actual tactile feeling, and still amount to a large portion of the peripheral devices such as keyboard of the computer.
According to the design of physical keys, a rubber dome is disposed between the key cap and the circuit board. When the user presses the key cap, the key cap presses the rubber dome and deforms, and further conducts the circuit board to output a signal for operating the key. According to conventional design, most rubber domes are half-hollowed sphere whose opening end is opposite to the circuit board, and directly enclosed by the circuit board. Thus, there is a closed space in the rubber dome, which hinders the user from pressing the key cap easily.